Hello Suhail,
I looked over your calculator vi and can see there are many issues.
1. Your while loop doesn't loop more than once because you have the "=" button wired to the "Run while True" terminator; you need to change the terminator to "Stop when True".
2. Your function button text, which is the button's "Label", "covers up" a lot of the button space, you have to click a corner of the button to operate it. Use the button "Caption" property to display the text, do not show the label.
3. You are trying to use the array search function to determine which function generated a non-zero result. The array search gives you the index into the array with your desired result, not the result itself. Even if you fix this, what happens if the result of the calculation is zero? It won't be found; even though the indicator will show zero, you may want a better way to determine which calculation was used.
4. Some of your calculations, like the trig functions, are made in both the True and False case check on the function button, these functions always generate a value and cause the array search to return the wrong index.
5. You may want to change the button mechanical actions to something like "latched when pressed" instead of "switch when pressed", then the vi will start with the buttons "off"; running this vi to test it requires you revert the buttons to default values before running again.
You could simplify this vi by using the event structure in the while loop to perform the selected calculation when one of the function buttons switches to True. You could update a shift register in the while loop with the value from the most recent calculation. There are several options here, I'm not sure what functionality you really need and want - do you need a separate display for every type of calculation? Waht do you really want displayed in the main indicator before the "=" key is pressed?
Good Luck - Brian
