Floating Point Precision

IBM 360/44:

One unusual feature of the Model 44's console was a rotary knob to select floating point precision; reducing the precision increased speed.

Funny story: this is actually how it's implemented in Javascript to this day.

kenshirriff:

Bizarrely, the units on the knob are bits in the significand, divided by 4. For comparison, modern floating point would be a setting of 6 for single precision and 13.25 for double precision.

The second console function was "operator intervention":

program debugging tasks such as examining and modifying memory or registers and setting breakpoints. The Model 30 console controls below were used for operator intervention. To display memory contents, the operator selected an address with the four hexadecimal dials on the left and pushed the Display button, displaying data on the lights above the dials. To modify memory, the operator entered a byte using the two hex dials on the far right and pushed the Store button. (Although the Model 30 had a 32-bit architecture, it operated on one byte at a time, trading off speed for lower cost.) The Address Compare knob in the upper right set a breakpoint.

If IDE developers were as obsessed with skeuomorphism as music software developers, this is what Xcode would look like:

Maybe that's not such a bad idea, actually. Xcode should have Winamp skins.

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6 Responses:

  1. cdavies says:

    > Maybe that's not such a bad idea, actually. Xcode should have Winamp skins.

    Just because you got out, doesn't mean you have to wish suffering on the rest of us.

  2. tfb says:

    > If IDE developers were as obsessed with skeuomorphism as music software developers [...]

    I have a trick when looking for music tools: buy the ones that don't look like a pastiche of a bit of hardware, the argument being that the people who have bothered to think about what a synthesizer interface might look like in a world where switches, knobs and faders are not the only practical way of adjusting parameters might also have thought harder about what a synth could sound like in such a world.

    I don't know if the trick works, but I have some interesting toys anyway.

  3. japh says:

    Ask (or not) and you shall receive...

    * https://archive.org/details/winampskin_Frequency_v5

    The future of IDEs has now arrived--developers, developers, developers! "Is that squire... on the fire? Mercy no sir, look closer, you'll notice it's grocer..."

  4. eswan says:

    "......This one goes to fourteen!"

  5. thielges says:

    Configurable precision is still used today though buried deep inside chips and with no direct user control.

    The amazingly awkward requirement to twist a dial before running a deck of cards shows how desperate we were for compute power back in the day. There must have been fun times when the operator forgot to reset precision back to the default. “This analysis worked fine yesterday! What went wrong?” (Proceeds to check to ensure cards are in right order)

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