hello people am new here.. and i started off coding.. i have few doubts. I want to roundoff a float value with no elements after the decimal point without using a lib function.

For example 16.25 = 16.00 :)

i tried

printf("%.0f,16.25); and it prints 17.. If i know the code for ceil function i could code my own from it.. And i also want to find the location of the decimal point :)

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Last Post by WaltP

printf("%.0f,16.25); and it prints 17..

not sure what you're talking about.

that will most certainly round it down and print "16"

printf() always prints the float value as a rounded value, to the nearest decimal place that you specify.

if you "really" want to round a value to the nearest decimal place, and store it permanently, then you need to:

muliply the float value by a power of 10, where the log10 of the mulitplier is the number of decimal places you want to round

cast it as an integer to drop all fractional values

divide it by the same power of 10 that you multiplied earlier

example:

``````double value = 16.75927;
double newVal = (int)(value * 100 + 0.5) / 100.0;

printf("original value             = %f\n\n",value);
printf("value rounded 2 decimal    = %f\n",newVal);``````

what if i dont want to typecast?

all i want is truncate a given floating point value (e.g.16.25=16). and not assigning the float value to integer & then copy the int value to float and find the position of decimal point in a given floating point value

if you only want to truncate, then do exactly what i said for rounding, but without adding +0.5

if you want a solution to do it without library functions *and* without typecasting, then we're talking about instructors demanding stupid programming tricks for trained monkeys. At which point you're on your own.

floatval= (int) floatval;

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