I need two decimal values without rounding off

Hi, I have a matrix which do contain decimal values.But I need just 2 decimals without rounding off the values.For example I have a value like 0.0194.My result should be 0.01.How can I do that?

Answer 1

[madhan ravi]

Hi try this:

a=floor(100 * 0.0194)/100
fprintf('%0.2f',a)

For more clarification click the link below:

https://www.mathworks.com/matlabcentral/answers/32169-how-can-i-format-a-percent-using-2-digits-after-the-decimal

Note:floor command was taken from Sir Walter.

I recently figured out a syntax you were looking for. Try this for sure:

format bank

[Walter Roberson]

>> f = 0.0194
f =
                    0.0194
>> format bank
>> f
f =
          0.02

format bank rounds; the user does not want to round.

[madhan ravi]

Oh thank you sir walter then I think the first option would be fine I guess? Am I correct or?

[Walter Roberson]

The user did not specify what they wanted done for negative values.

It is not clear what the user wants to do with the value, whether they want to use it in further calculation or want to display it or create it as a character vector. If they do want to use it for further calculation, I hope they take into account that there is no way to exactly represent most multiples of 1/100 in binary floating point.

[madhan ravi]

Yes sir walter I understand your point. Could you please answer my question regarding subs?

[Image Analyst]

You mean the question about the first option being fine? Yes of course it would work - it's basically the answer I gave, before you realized your first answer with sprintf() (which gave 0.02) didn't work and changed it. And then Walter added the option of floor, which handles the rounding in a different direction for negative numbers. So, yes fix() and floor() both can work - just depends on what they want. If there are no negative numbers, it doesn't matter and you can use either fix() or floor().

"format bank" just changes how the numbers are displayed but does not actually change the number at all like fix/floor does.

Walter's last sentence is also important to understand, as is this related FAQ: https://matlab.wikia.com/wiki/FAQ#Why_is_0.3_-_0.2_-_0.1_.28or_similar.29_not_equal_to_zero.3F

[madhan ravi]

Thank you for the information sir.

Answer 2

[Image Analyst]

Use fix:

v = 0.0194
v2 = fix(100 * v)/100

[Walter Roberson]

If your value were -0.0194 and you want the answer -0.01 then fix() is the right thing to use. If you wanted -0.02 instead (the 1/100th that is less than or equal to the number) then you would use floor() instead of fix()