function IsNumeric()

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Barbie
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function IsNumeric()

Post by Barbie »

Has anyone a function IsNumeric() handy? I don't want to reinvent the wheel…
NXPUtil.IsNumeric() does not respect the dot.

The function should recognise the following example strings as numeric (too lazy to create a regex for this): :pfff:
1.23
1
+1
+1.23
-1
-1.23
Cherry on ice would be returning the value also:
function bool IsNumeric(coerce s as string, Optional out float value)
"If Origin not in center it be not in center." --Buggie
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snowguy
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Re: function IsNumeric()

Post by snowguy »

Buggie
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Re: function IsNumeric()

Post by Buggie »

Code: Select all

f = float(s);
ret = f != 0;
if (!ret) {
    // do some simple checks if need distinguish false and 0 value as input.
}
return ret;
Side effect it accept values like "12345 some text".
If you not need it, you can later check Something like that:
if (float(s) == float(s $ "9999")) die("Bad chars at end");
OFC in some edge cases like "1.00000000" it make false positive, but it good enough for most cases.
Can be improved as:

Code: Select all

f = float(s);
return f != 0 || f != float(s $ "999");

Or even:

Code: Select all

f = float(s);
return f != float(s $ "999");
Fit for most cases. except some really edge cases, when numbers specified too precise for float so append at end not change it.
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PrinceOfFunky
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Re: function IsNumeric()

Post by PrinceOfFunky »

Convert the String to float, then the resulting float back to String and compare the two strings, if they are equal it's numeric.
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Barbie
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Re: function IsNumeric()

Post by Barbie »

PrinceOfFunky wrote: Thu Jul 13, 2023 1:40 pm Convert the String to float, then the resulting float back to String and compare the two strings, if they are equal it's numeric.
Thanks, but string(float("1.23")) is something like "1.2300000" AFAIR. I already run into such.
"If Origin not in center it be not in center." --Buggie
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PrinceOfFunky
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Re: function IsNumeric()

Post by PrinceOfFunky »

Barbie wrote: Thu Jul 13, 2023 6:52 pm
PrinceOfFunky wrote: Thu Jul 13, 2023 1:40 pm Convert the String to float, then the resulting float back to String and compare the two strings, if they are equal it's numeric.
Thanks, but string(float("1.23")) is something like "1.2300000" AFAIR. I already run into such.
Then just compare the same amount of characters, like left(x, strLen(x)) and left(y, strLen(x)).
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ExpEM
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Re: function IsNumeric()

Post by ExpEM »

Have you got a working solution?
It wouldn't be an ideal way but you could parse the string one char at a time.

Code: Select all

Psudo code.

While loop
	if first char in string
		if char = (+,-,.,0,1,2,3,4,5,6,7,8,9)
			Keep going
		else
			return false
	
	else
		if char = (.,0,1,2,3,4,5,6,7,8,9 and "." hasn't already occurred)
			Keep going
		else
			return false
			
	if no more char
		return true
	else		
		next char
	
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