2016년 11월 25일 금요일

equals


Hello,
whats the diferent between the blue and the green equal block?

No matter what color block i choose?

Best regards

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as far as I know there is no difference
Taifun

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There is a significant difference in the two blocks.  The blue equals is used ONLY with mathematical relationships.  The green equals can deal with symbolic and text relationships .

These are the logic blocks     described in detail here http://appinventor.mit.edu/explore/ai2/support/blocks/logic.html    The green = sign works like this:

    Tests whether its arguments are equal.
    • Two numbers are equal if they are numerically equal, for example, 1 is equal to 1.0.
    • Two text blocks are equal if they have the same characters in the same order, with the same case. For example, banana is not equal to Banana.
    • Numbers and text are equal if the number is numerically equal to a number that would be printed with that text. For example, 12.0 is equal to the result of joining the first character of 1A to the last character of Teafor2.
    • Two lists are equal if they have the same number of elements and the corresponding elements are equal.
    Acts exactly the same as the = block found in Math

These are the Math blocks.   They are the blue blocks.  All the Math blocks are described here  http://appinventor.mit.edu/explore/ai2/support/blocks/math.html  

The blue Math block works like this:
Tests whether two numbers are equal and returns true or false.

Where   variable1 and variable2 are numbers,    if variable 1 = variable 2 then ....

Regards,
Steve

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thank you @SteveJG
however the blue = block can also work with alphanumeric values...


Taifun

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