casio fx-3900pv

one of a few last generation non-formula entry machines. 10+2 display, programmable and can perform numerical integration, 2d statistics and linear regression. the keys are rubber. there are 6 `K' memories plus the normal memory. hyperbolics are absent, so are fractions. now why is that.

the programmability is not so hot. there are 4 program slots p1-p4 designed mainly to hold formulae because conditional and non-conditional jumps are always back to the start of the program. this limits their usefulness. they are handy, however, to host formulae for the built-in numerical integration.

the programming is not totally blind because the display is quite good at showing the program function at each step. it does this on the top line above the numbers.

although the display is better, accuracy is not better than the fx-100. it can perform trigs on values greater than 1440 degrees.