float vs double

[Chuan Chee]

I have been using "double" almost extensively on a Personal Iris 4D/20.
I am curious about the advantages/performance of using "float".  Yes I
realize that "float" has less precision but let's assume that I only
need float precision.

The assumptions I have about float are:
(1) The floating point accelerator computes float expressions faster
    than double expressions.
(2) float takes half the amount of storage.

I am posting this to confirm my assumptions and maybe get some statistics.
Are there other advantages/performance considerations?

How fast/slow is converting between float and double?

One other thing - I am compiling with:
    cc -g -signed -Zg

...Chuan Chee
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