I am trying to find a percentage using the Big Number library from @openzeppelin/test-helpers Here is the code: var someVarABC = new BN('2706'); var someVarDEF = new BN('5060584'); var total = someVarABC.add(someVarDEF); var percentage = (someVarDef.div(total)).mul(new BN('100')); The error I get…

let abc = new BN('2706'); let def = new BN('5060584'); let total = abc.add(def); let percentage = def.mul(new BN('100')).div(total); This works. Note you can also do def.muln(100).

[image] jayman27: var percentage = (someVarDef.div(total)).mul(new BN('100')); try this var percentage = someVarDef.mul(100); percentage = percentage.div(total); If you need to use BN then do it, but so far I haven't had to use the BN library as my numbers aren't "that" big.

I had to use BN because I was getting “invalid array length” error. When I switch the 100 to a BN I got the same error in my original post. Here is the new code I tried: var percentage = someVarDef.mul(new BN('100')); percentage = percentage.div(total); Error: Assertion failed …

I apologize. It was my embarrassing error where I didn’t assign my total var the new value after using the add function. total.add(someVarDef); Instead of: total = total.add(someVarDef); Which resulted in me dividing by zero :dizzy_face: Thank you for the help

I would also like to note that “Error: Assertion failed” is a less-than-helpful error message. Got XXX, expected YYY would be helpful.

Percentages with Big Numbers Truffle Test

Support

Yoshiko May 14, 2021, 10:08am 4

This might be a specific OZ question that needs to answer. @frangio Maybe you know more about this specific import? Thank you for the assistance.

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Percentages with Big Numbers Truffle Test

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