Ivy

The latest version crashes at launch on both my iPhone 6S Plus and iPad Air. I noticed this after updating to iOS 10. I haven't used the app in a while, so I don't know the last iOS version on which it did work.

I don't know... got some pretty big numbers....

I don't do much complex math, but very occasionally I need to do something with high precision, and it's great for that. The UI is probably the weakest part, you can't easily reuse your last line, you have to copy and paste it, or if you're proactive, assign it to a variable. The extra buttons for the operations don't insert where the cursor is, they always insert at the end of the line. But I doubt the quirks will be fixed. it's useful regardless, and I'm very glad it exists!

Wonderful and powerful little calculator, and a nice tribute to Ken Iverson in the name. Would love to see a full version of J.

I have a PhD in math, have taught it, and used it for years as a statistician. Ivy uses right-associative order of operations. I don't understand how this is an advantage, or is even desirable. From the documentation: "Unlike in most other languages, operators always have the same precedence and expressions are evaluated in right-associative order. That is, unary operators apply to everything to the right, and binary operators apply to the operand immediately to the left and to everything to the right. Thus, 3*4+5 is 27 (it groups as 3*(4+5)) and iota 3+2 is 1 2 3 4 5 while 3+iota 2 is 3 4 5. A vector is a single operand, so 1 2 3 + 3 + 3 4 5 is (1 2 3) + 3 + (3 4 5), or 7 9 11. As a special but important case, note that 1/3, with no intervening spaces, is a single rational number, not the expression 1 divided by 3. This can affect precedence: 3/6*4 is 2 while 3 / 6*4 is 1/8 since the spacing turns the / into a division operator. Use parentheses or spaces to disabiguate: 3/(6*4) or 3 /6*4."

A great app! Much more convenient, less expensive, and more portable than the Anderson/Jacobson 841 terminal I learned this language on. As far as I can tell, Ivy is the ONLY extended precision/arbitrary precision calculator on the whole iOS store. E.g., if you want to know the exact value of 1000 factorial, Ivy will tell you. The calculator appears to use *78* digits of internal precision for floating point values- but only displays 12 of them. Is there a way to change the output precision?

Refreshing blast from the past. APL is a great language for vectors and arrays, and it is cool indeed to see a nicely implemented subset of it here. Very incomplete, and I am not sure how useful yet, but very cool. Thanks!

Great for calculating big numbers that would usually give you an error message. Also good if you're doing really sophisticated things with it.