JPH06348473A - Method for preparing data flow diagram - Google Patents

Abstract

PURPOSE:To automatically generate a data flow diagram which is not inconsistent with the depending relation with input and output (I/O) data to be sequentially given. CONSTITUTION:A memory device 4 includes a generated data flow diagram 41 and a process I/O collecting table 42. The table 42 expresses the collection of input data depending upon each process on the data flow diagram 41 and the collection of output data depending only upon the input data. A correcting operation generating part 32 sequentially inputs the addition or deletion of I/O data pairs through a depending relation input part 31, refers to a process I/O collection given through a process collection managing part 34 and instructs a data flow chart editing part 33 to execute the correcting operation of the diagram 41. In addition, the generating part 32 instructs the managing part 34 to update the table 42.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of creating a data flow diagram used for software development, requirement analysis, etc., and more specifically, it sequentially gives an instruction of addition / deletion for a pair of input data and output data. The present invention relates to a method for creating a data flow diagram, which enables automatic creation of a data flow diagram sequentially by giving the data flow diagram.

[0002]

2. Description of the Related Art A data flow chart is a flow chart showing the correlation between a process and its input / output data, and is used for describing required specifications of software. Conventionally,
As a method for automatically creating this kind of data flow diagram, a method has been proposed in which a dependency between input and output data is uniquely defined in advance, and a unique data flow diagram is automatically created based on it. M., “An Algebra for D
ata Flow DiagramProcess Decomposition "IEE
E trans. on SE, Vol. 14, No. 2, pp. 169
-183, 1988).

[0003]

The conventional automatic data flow diagram creation technique described above is based on the premise that the details of the input / output data dependencies are defined in advance. There is a problem that it cannot be applied when trial and error examination is necessary, such as when the details of is not determined or when a part of the dependency is changed. In addition, even if you change part of the input / output data dependency, you should not modify part of the data flow diagram created based on the input / output relationship before the change, but based on the input / output relationship after the change. It was necessary to recreate all data flow diagrams.

An object of the present invention is to eliminate such a drawback of the prior art, to make it possible to sequentially provide a dependency relationship between input and output data, and to sequentially and automatically create a data flow diagram. Is to

[0005]

According to the present invention, for each process on a data flow diagram that has already been created, a set of input data on which the process depends and a set of output data on which only the input data depends. Is managed as a process input / output set, and addition or deletion of an input / output data pair consisting of a dependency set of one input data and one output data is sequentially input, and the input / output data input The data flow diagram is modified based on the pair and the process input / output set corresponding to the already created data flow diagram, and the process input / output set is updated in accordance with the correction result, and sequentially. This enables the sequential creation and modification of data flow diagrams that are consistent with the given input / output data dependencies.

[0006]

A set (α, θ) consisting of a set α of inputs from the outside reaching the process P on the data flow diagram and a set θ of outputs from the process P to the outside is called a process input / output set for the process P. . This process input / output set is managed for all processes on the data flow diagram.

An editing operation procedure for adding a dependency relationship to a data flow diagram is as follows.

(1) A process of inputting only a from the outside is extracted as follows. (1-1) Process P that satisfies the following determination condition 1 is
It is extracted as a process of inputting a from the outside. <Judgment condition 1> The input set of the process P is the minimum input set having a as an element among the input sets of all processes (1-2) The input set of the process that inputs a from the outside is a Check whether input other than is input from outside.
That is, when the following determination condition 2 is satisfied, it is determined that an input other than a is input from the outside. Otherwise, a
It is determined that no other input is input from outside. <Judgment condition 2> The input set of the process P is not the minimum input set having b as an element for any input b other than a in the input set of all processes. However, when an input other than a is input from the outside, it is divided into a process of inputting only a from the outside and a process of inputting other than a as follows. That is, the input / output set of P is (α ∪ {a},
θ), the process of inputting only a from the outside having the input / output set ({a}, θ) and the input / output set (α,
A process for inputting an input other than a having θ) from the outside is generated. Also, the process P is deleted. If nothing other than a is input from the outside, the process is not divided.

(2) A process for outputting only z to the outside is extracted as follows. (2-1) Process P satisfying the following determination condition 3 is
Extract as a process that outputs z to the outside. <Judgment condition 3> The input set of the process P is the minimum output set that is an element of the output sets of all processes (2-2) The output set of the process that outputs z to the outside is other than z Check whether the output is output to the outside. That is, when the following determination condition 4 is satisfied, it is determined that outputs other than z are output to the outside. If not, it is determined that outputs other than z are not output to the outside. <Determination condition 4> The output set of the process P is not the minimum output set having y as an element for any output y other than z in the output set of all processes. When an output other than z is output to the outside, it is divided into a process for outputting only z to the outside and a process for outputting other than z as follows. That is, when the input / output set of P is (α, θ∪ {z}), the process of outputting only z to the outside having the input / output set (α, {z}) and the input / output set (α, θ) ) Is output to the outside except z. Also, the process P is deleted. If only z is output to the outside, the process is not divided.

(3) When a data flow from a process that inputs only a from the outside to a process that outputs only z to the outside is added, processes that are equivalent to each other are integrated as follows. (3-1) First, the input / output sets of the process that inputs only a from the outside and the process that outputs only z to the outside are modified as follows. That is, a is added to the input set of the process that outputs only z to the outside, and z is added to the output set of the process that inputs only a from the outside. (3-2) Extract processes equivalent to each other as follows. That is, regarding the processes P and Q, when the following determination condition 5 is satisfied, it is determined that the processes P and Q are equivalent to each other. <Judgment condition 5> The set of input / output sets of the process P is (α,
When the set of input / output sets of θ) and Q is (β, ζ), α
= Β or θ = ζ If processes P and Q are mutually equivalent processes, the input / output set (α ∪ β, θ ∪ ζ) obtained by integrating the sums of the respective input sets and output sets is integrated. It is the input / output set of the process. At this time, delete processes P and Q,
Add an integration process.

(4) The data flow relating to the process of inputting a from the outside and the process of outputting z to the outside is modified as follows. (4-1) Process of inputting a from the outside, and
Regarding the process of outputting z to the outside, the following judgment condition 6
When is satisfied, add data flow between processes. <Judgment condition 6> The set of input / output sets of the process P is (α,
When the set of input / output sets of θ) and Q is (β, ζ), the following conditions must be satisfied: 1) α ⊆ β and θ ⊇ ζ 2) α ⊆ γ ⊆ β and θ ⊇ Input / output set (γ,
There is no process with δ) FLOW (P, Q) indicates that the determination condition 6 is satisfied. (4-2) Process of inputting a from the outside, and
For the process of outputting z to the outside, the data flow with the outside is modified as follows. An input data flow from the outside is generated for the processes created in (1-2) and (2-2). That is, if the input set of the created process is the minimum input set including the element e for the element e, a data flow for inputting the element e from the outside is created. Also, an output data flow to the outside is generated for the processes created in (1-2) and (2-2). That is, if the output set of the created process is the minimum output set including the element x for the element x, a data flow for outputting the element x to the outside is created.

An editing operation procedure for deleting a dependency from a data flow diagram is as follows. Here, it is assumed that the system input / output relationship (a, z) is deleted from the data flow diagram.

(1) A process that depends on a and affects z is extracted. That is, a process in which the input set of each process contains a and the output set contains z depends on a, and z
Extract as a process that affects.

(2) Divide into processes that depend on a and processes that affect z. That is, depending on a, z
The input / output set of the process that influences (α∪ {a}, θ∪
When {z}), the process is divided into a process having ({a}, θ) as an input / output set and two processes having (α, {z}) as an input / output set.

(3) A data flow relating to a process dependent on a and a process affecting z is generated as follows. (3-1) For the process P that depends on a and the process Q that affects z, when FLOW (P, Q) is established, a data flow from the process P to the process Q is created. (3-2) The data flow with the outside for the process that depends on a and the process that affects z is modified as follows. An external input data flow is generated for the process created in (2). That is, if the input set of the created process is the minimum input set including the element e for the element e, a data flow for inputting the element e from the outside is created. Also, (2)
Generate an output data flow to the outside for the process created in. That is, if the output set of the created process is the minimum output set including the element x for the element x, a data flow for outputting the element x to the outside is created.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a functional block diagram showing a data flow diagram creating apparatus according to an embodiment of the present invention. The data flow diagram creation device includes an input device 1 such as a keyboard, a display device 2 such as a CRT display, a processing device 3, and a memory device 4. Here, the processing device 3 uses the dependency relationship input unit 3
1, correction operation generation unit 32, data flow diagram editing unit 33,
It is configured by the process input / output set management unit 34. The memory device 4 stores a data flow diagram 41 that has already been generated and a process input / output set table 42 that describes the process input / output set of each process on the data flow diagram.

The dependency input unit 31 includes the input devices 1 to 1
Addition or deletion of an input / output data pair consisting of a set of dependency relationships between one input data and one output data is sequentially input. Based on the input / output data pair and the process input / output set for the data flow diagram from the process input / output set management unit 34, the correction operation generation unit 32 creates a data flow diagram required for adding or deleting a dependency relationship. Generate a fix operation. This generation procedure will be described later. The data flow editing unit 3 corrects the data flow diagram 41 based on the generated correction operation, and further displays the data flow diagram on the display device 2. The process input / output set management unit 34 manages, as a process input / output set table 42 on the memory device 4, a set of input data necessary for each process of the data flow diagram and a set of output data that influences the process, and generates a correction operation. The process input / output set table 42 is referred to / updated based on an instruction from the unit 32, and is displayed on the display device 2 as necessary.

FIG. 2 shows an example of a data flow diagram. (A) is a data flow diagram without input / output dependency (a, z), and (b) shows input / output dependency (a, z). It is a certain data flow diagram. Here, if the dependency (a, z) is added in the data flow diagram of (a), it matches the data flow diagram of (b). On the contrary, when the dependency (a, z) is deleted from the data flow diagram of (b), it matches the data flow diagram of (a).

Next, taking the data flow diagram of FIG. 2 as an example,
The procedure for generating the correction operation of the data flow diagram in the correction operation generating unit 32 of FIG.

FIG. 3 is a modification operation in the modification operation generation unit 32 when the dependency (a, z) is added to the data flow diagram of FIG. 2A to modify the data flow diagram of FIG. 2B. It shows a generation procedure. As a premise, the modification operation generation unit 32 is additionally provided with the dependency relationship pair (a, z) from the dependency relationship input unit 31, and the process input / output set management unit 34 displays the data flow diagram of FIG. It is assumed that the input / output set of each process is given.

(1) Extracting a process for inputting only a from the outside Referring to the input / output set of each process given from the process input / output set management unit 34, it is as follows. P1: ({b}, {x, y, z, w}) P2: ({a, b}, {y, w}) P31: ({a, b, c}, {y}) P32: ( {B, c}, {z, y}) P4: ({a, b, d}, {w}) (1-1) Extract the process of inputting a from the outside. Of the input / output sets of each process, the input set of P2 is the smallest in the input set having a as an element, so P2 is extracted as the process of inputting a from the outside. (1-2) Process of inputting only a from the outside, and a
Divide into processes that input other than. P2 does not need to be divided because it is not input from outside except a. However,
Note that there is a data flow from P1 to P2 that inputs b from the outside, so the input set of P2 is {a, b}.

(2) Extract the process that outputs only z to the outside (2-1) Extract the process that outputs z to the outside.
Among the input sets of each process, the output set of P32 is the smallest output set having z as an element, so P32 is extracted as a process that outputs z to the outside. (2-2) It is divided into a process for outputting only z to the outside and a process for outputting other than z. P32 does not need to be divided because it does not output other than z to the outside. Note, however, that there is a data flow from P32 to P31 that outputs y, so the output set for P32 is {z, y}.

(3) When a data flow from a process that inputs only a from the outside to a process that outputs only z to the outside is added, processes that are equivalent to each other are integrated. (3-1) Only z is output to the outside. A is added to the input set of the process to be input, and z is added to the output set of the process to which only a is input from the outside. If z is added to the output set of P2, the input / output set of P2 becomes ({a, b}, {y, w,
z}). If z is added to the input set of P32, P
The 32 input / output sets are ({b, c, a}, {z, y})
Becomes (3-2) Processes that are equivalent to each other are extracted, and the sum of the input set and the output set is integrated into the input / output set of the process. Since the input set of P31 is {a, b, c}, it matches the input set of P32. Therefore, an input / output set ({a, b, c}, {z, y}) of the process in which the sum of the input set and the output set is integrated is created, and is set as the input / output set of the integrated process P3. Also, the input / output set for P31 and P32 is deleted. At this time, P3
Is added, and an edit operation for deleting P31 and P32 is generated.

(4) Corrected the data flow relating to the process of inputting a from the outside and the process of outputting z to the outside (4-1) The process of inputting a from the outside, and
Modify the data flow between processes for processes that output z to the outside. The process of inputting a from the outside is P2. The process of outputting z to the outside is P
It is 3. At this time, the input / output set of P2 is ({a,
b}, {y, w, z}), and the input / output set of P3 is ({a, b, c}, {z, y}). These input / output sets are the data flow existence conditions FLOW (P2, P
Since 3) is satisfied, an edit operation for creating the data flow from P2 to P3 is generated. (4-2) Process of inputting a from the outside, and
Modify the data flow between processes for processes that output z to the outside. The input set {a, b} of P2 is a
Since it is the minimum input / output set including, an edit operation for inputting a into P2 from the outside is generated. Since the output set {z, y} of P3 is the minimum output set including z, an edit operation for outputting z from P3 to the outside is generated. Since the input set {a, b, c} of P3 is the minimum input set containing c, an edit operation for externally inputting c to P3 is generated. Since the output set {z, y} of P3 is the minimum output set including y, an edit operation for outputting y from P3 to the outside is generated.

The data flow diagram editing unit 33 corrects the data flow diagram of FIG. 2A as shown in FIG. 2B in accordance with the correction operation instruction generated by the correction operation generating unit 32. Similarly, the process input / output set management unit 34 updates the process input / output set based on the instruction from the correction operation generation unit 32.

FIG. 4 is a modification operation in the modification operation generation unit 32 when the dependency (a, z) is deleted in the data flow diagram of FIG. 2 (b) to modify the data flow diagram of FIG. 2 (a). It shows a generation procedure. Here again, as a premise, the modification operation generation unit 32 is given the dependency relationship pair (a, z) as a deletion from the dependency relationship input unit 31 and the process input / output set management unit 34 receives the data of FIG. 2B. It is assumed that the input / output set of each process in the flow diagram is given.

(1) Extracting a Process that Depends on a and Affects z Referring to the input / output set of each process given from the process input / output set management unit 34, it is as follows. P1: ({b}, {x, y, z, w}) P2: ({a, b}, {y, w, z}) P3: ({a, b, c}, {z, y} ) P4: ({a, b, d}, {w}) The process of inputting a from the outside is P2, because P2 has the smallest input set including a. The input / output set of P2 is ({a, b}, {y, z, w}). The process of outputting z to the outside is P3 because PS has the smallest output set including z. In the case of P3,
Not only is z output to the outside, but y is also output to the outside.

(2) Divide into processes that depend on a and processes that affect z. Since P2 does not input anything other than a from the outside, it is not necessary to divide the process. In this case, z is deleted from the output set of the process P2 in which only a is input from the outside. That is, the input / output set of P2 is ({a, b}, {y, w}). This is different from the I / O set of other processes. P
Since 3 outputs y in addition to z to the outside, it needs to be divided into the following two. First, from the output set of P3, z is set so that the output set of the process dependent on a does not include z.
A process having an input / output set in which is deleted is P31.
That is, the input / output set of P31 is ({a, b, c},
y}). Next, a process having an input / output set obtained by deleting a from the input set of P3 is defined as P32 so that the input set of the process affecting z does not include a. That is, the input / output set of P32 is ({b, c}, {z, y})
Is. At this time, an edit operation for deleting P3 and adding P31 and P32 is generated.

(3) Modify the data flow related to the process dependent on a and the process affecting z (3-1) Modify the data flow between processes for the process dependent on a and the process affecting z. . The process of inputting a from the outside is P2.
The processes that affect z are P31 and P32.
At this time, the input / output set of P2 is ({a, b}, {y,
w}), the input / output set of P31 is ({a, b, c},
{Y,}), the input / output set of P32 is ({b, c},
{Z, y}). First, the input / output set of P32 and P31 is the existence condition FLOW (P32, P3 of the data flow).
Since 1) is satisfied, an edit operation for creating the data flow from P32 to P31 is generated. Next, P2 and P
31 input / output sets are data flow existence conditions FLOW
Since (P2, P31) is satisfied, an edit operation for creating a data flow from P2 to P31 is generated. Finally, the input / output set of processes P1 and P32 that influences z is the existence condition FLOW (P1, P32) of the data flow.
Since the above condition is satisfied, an edit operation for creating the data flow from P1 to P32 is generated. (3-2) Modify the data flow with the outside for the process that depends on a and the process that affects z. Since the output set {y} of P31 is the minimum output set including, an edit operation for outputting y from P31 to the outside is generated. Since the output set {z, y} of P32 is the minimum output set including y, an edit operation for outputting y from P31 to the outside is generated. Since the input set {b, c} of P32 is the minimum output set containing c, an edit operation for inputting c to P32 from the outside is generated.

The data flow diagram editing unit 33 corrects the data flow diagram of FIG. 2B as shown in FIG. 2A according to the correction operation instruction generated by the correction operation generating unit 32. Similarly, the process input / output set management unit 34 updates the process input / output set based on the instruction from the correction operation generation unit 32.

[0032]

As described above, according to the present invention,
Correct data flow diagram that does not contradict input / output data dependency that is given sequentially can be automatically generated, so it is not necessary to completely define the input / output data dependency in advance, and trial and error creation work of data flow diagram is possible. There is an advantage that the efficiency of can be changed significantly.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing an embodiment of the present invention.

FIG. 2 is an example of a data flow diagram for explaining the present invention.

FIG. 3 is a diagram showing an example of an edit operation generation procedure for adding a dependency entered in a data flow diagram.

FIG. 4 is a diagram showing an example of an editing operation generation procedure for deleting a dependency input from a data flow diagram.

[Explanation of symbols]

 1 Input Device 2 Display Device 3 Processing Device 31 Dependency Relationship Input Unit 32 Correction Operation Generation Unit 33 Data Flow Diagram Editing Unit 34 Process Input / Output Set Management Unit 4 Memory Device 41 Data Flow Diagram 42 Process Input / Output Set Table

Claims (1)

[Claims] 1. A method for automatically creating a data flow diagram in which a correlation between a process and its input / output data is represented by a flow diagram, in which input data on which the process depends on each process on the already created data flow diagram. And a set of output data depending only on the input data are managed as a process input / output set, and an input / output data pair consisting of a set of dependency relationships of one input data and one output data is added or Deletes are sequentially input, and the data flow diagram is corrected based on the input / output data pair and the process input / output set corresponding to the already created data flow diagram, and the correction result is corresponded. And then updating the process input / output set.