Your code can be simplified to:
NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
[formatter setNumberStyle:NSNumberFormatterDecimalStyle];
[formatter setMaximumFractionDigits:0];
double text1 = [textField1.text doubleValue];
double text2 = [textField2.text doubleValue];
double text3 = [textField3.text doubleValue];
double text4 = [textField4.text doubleValue];
double text5 = [textField5.text doubleValue];
double text6 = [textField6.text doubleValue];
double VolumePerMtrLitres = ((M_PI_4 * (text1 / 1000) * (text1 / 1000)) - (M_PI_4 * (text2 / 1000) * (text2 / 1000))) * text5 * 1000;
NSString *numberAsString = [formatter stringFromNumber:@(VolumePerMtrLitres)];
volumePerMeterLitreAnswer.text = [NSString stringWithFormat:@"%@ ltr.", numberAsString];
double LubricationPumpCapacity = text5 / 1000 * [volumePerMeterLitreAnswer.text doubleValue];
NSString *numberAsString2 = [formatter stringFromNumber:@(LubricationPumpCapacity)];
pumpSpeedAnswer.text = [NSString stringWithFormat:@"%@ litre per min.", numberAsString2];
double VolumePerPipeLitre = [volumePerMeterLitreAnswer.text doubleValue] * text3;
NSString *numberAsString3 = [formatter stringFromNumber:@(VolumePerPipeLitre)];
volumePerPipeLitreAnswer.text = [NSString stringWithFormat:@"%@ ltr.", numberAsString3];
double VolumeForDriveLitres = [volumePerMeterLitreAnswer.text doubleValue] * text4;
NSString *numberAsString4 = [formatter stringFromNumber:@(VolumeForDriveLitres)];
volumeForDriveLitreAnswer.text = [NSString stringWithFormat:@"%@ ltr.", numberAsString4];
Notice the user of M_PI_4
to replace your 3.14159 / 4
. Also notice the use of the @(someVariable)
syntax instead of using [NSNumber numberWithXXX:someNumber]
.