The application of causality diagram in black box test

Representation symbol for causality diagram (reason → result)

Equal:

if (C) then Ef

Non -:

if (! C) Then Ef

With: if (C1 && C2 && C3)

Then Ef

Or: if (C1 | | C2) Then Ef

Exclusive: Exclusive

Either C1 or C2 or C3

C1,C2,C3 will not be set up at the same time, there can only be one

Inclusive:at least C1 or C2

Must present

C1,C2 at least one is 1 and cannot be zero at the same time

REQUIRE:C1 requires C2

C1 is 1 o'clock, C2 must be 1, i.e. C1 is 1 o'clock, C2 cannot be 0

Only One:one, and only one of C1 and C2

C1 and C2 must have one, and only one is 1

MASKING:EF1 Masks Ef2

Indicates that EF1 is 1 o'clock, Ef2 is forced to 0

Example Analysis:

Product Description: There is a vending machine software that handles boxed drinks with a unit price of 1.5 yuan. If you invest 1.5 yuan coins, press "Cola", "Sprite", or "black tea" button, the corresponding drink will be sent out. If you invest in a 2-dollar coin, return the 5-point coin at the same time you send the drink.

Reason:

1. Invest 1.5 yuan Coins 2. Invest 2 yuan Coin 3. Press the "Cola" button 4. Press "Sprite" button 5. Press the "Black tea" button

Results:

1. Return the 5-point coin 2. Send out "cola" Drink 3. Send out "Sprite" Drink 4. Send "black tea" drink

The application of causality diagram in black box test