|HP 35s Review|
Message #1 Posted by Will Rutherdale on 12 Sept 2007, 12:56 a.m.
I've been using HP calculators for decades and own several. Last summer I tried updating to newer models, and have acquired a 33s, a 50g, and now a 35s.
I want a calculator with a good mix of discrete and scientific capabilities, with a convenient user interface.
After a couple of days of trying the 35s out, I have some comments. These are just my personal usability concerns. I realise the calculator has already been released and probably won't be changed.
This is my first posting here. I hope they formatting comes out okay.
- adds logic operators (compared with 33s)
- good notation (i / theta) for entering complex numbers
- nicer keyboard layout than 33s
- good that funny mode keys are gone
- arrow keys are better
- big ENTER key is nice to see again
- better look and feel
- addition of extra units and physical constants is very useful
Problems (in order of decreasing priority)
- forced to fish out the 'h' suffix when entering a hex number,
even when in hex mode
- this is very inconvenient if you want to enter a lot of
- it takes too many keystrokes to get that 'h' suffix, which
should be implicit in hex mode
- user is now forced to enter a mantissa part for a number in
- standard interpretation in HP calculators for decades has
been to default to 1
- for instance 'e2' is taken as '1e2' in older models
- this is a great keystroke saver and has been in place for
decades in all HP calculators, up to and including the 50g
and the 33s
- sanity check: entering the number 1000 in scientific notation
should reduce the number of keystrokes
- sometimes the calculator misses a typed key
- overzealous debouncing?
- sqrt key gives 'invalid data' for complex numbers or negative
numbers entered as a complex number
- inconsistent with general ability to use transcendental
functions on complex
- sqrt is easy to implement in complex
- y^x key does it anyway when you give an exponent of .5
- there is no way to extract real and imaginary parts of a complex
- location and labelling of hex digits a to f
- I realise that layout decisions are not easy, but placing
them two rows below the register labels A to D is a bit odd
- assuming they hold to the layout, it would be better to at
least add some special labels in a different colour for
the hex a to f
- additional logic operators would be useful: shift, rotate, etc.
- compare with 16C or 50g
- new vector data type is very thinly supported
- no real power to it, just addition of vectors and
multiplication by a scalar
- it complains on input of a vector of length 0 but not a
vector of length 1
- 2*2 lin. solve and 3*3 lin. solve are badly done
- user has to fuss with a list of storage registers
- better idea: let user enter a set of vector objects into
the stack and let calculator operate on those
- for instance, 4 length-3 vectors would suffice for input to
a 3*3 lin. solver
- E key (for Enter Exponent) would be better labelled EE or EEX
- this would avoid confusion with the other E keys
- would stand out better
- when complex numbers are displayed in polar form, it would be
useful if the 'theta' character could be rendered differently
so as not to resemble zero and eight so much
- there should be a way to view complex numbers to greater
- see for instance how this is done in the 15C
- also compare with the scrolling view of large binary
numbers in the 35s
The 35s has look-and-feel improvements over the 33s and some functionality improvements. However, some interaction issues that affect everyday usage appear to have slipped through.
The 35s ought to be a convenient everyday use alternative to the bigger and more sophisticated 50g, but the 35s has limitations that leave the 50g more suitable for everyday use.