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Float comparison

I am ashamed to ask about this, but I am running iOS 6.1 and the following line returns False:

if ([[UIDevice currentDevice].systemVersion floatValue] >= 6.1)

still returns True:

 if ([[UIDevice currentDevice].systemVersion floatValue] >= 6.1f)

Why?

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3 answers

After a bit of reading, my understanding of the reason for this is as follows:

• C treats numbers like 1,2 as doubles and if they are modified with f eg 1.2f as floating • Neither doubles nor floats can be internally represented by the system with 100% accuracy • Representation errors for floats are higher than for doubling

Therefore, comparing a float with a double will basically lead to misleading results. For non-critical systems, a comparison of 2 floats is sufficient.

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Before comparison, the floats are thrown before doubling. A value of f indicates the number of decimal places. You compare two different numbers when you change the number of decimal places

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In the first version, systemVersion is converted from float to double and its value depends on how many bits you use to represent it.

In the second you compare two floats

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