Real Number to a string conversion so I can format my output in a Grid

Question

Was looking for something like Matlab's num2str function. I'm trying to use Grid to format output from a print statement, but some of the cells are complex like

"distance result = ", list[[2]], " meters "

The Print function has no problem with that

Print["distance result = ", list[[2]], " meters "]
Print["time result = ", list[[3]], " days "]

but if I try

Grid[{{"distance result = " <> IntegerString[list[[2]]]}," meters "},{"time result = " <> IntegerString[list[[3]]]," days "}},Alignment-> Left]

This only works if list[[2]] and list[[3]] are integers. How do I do this if list contains real numbers, i.e., IntegerString no longer works? I would like meters and days to be vertically aligned. I think I need to intermix text and real numbers inside a single grid cell. Maybe there is a better way to format outputs? Do I put separate Print statements inside each Grid cell? Not sure how to get properly formatted multi-line output in notebooks.

Answer 1

You need to use ToString:

list = {1.5, 2.5, 3.5};
Grid[{{"distance result = " <> ToString[list[[2]]], " meters "}, 
      {"time result = " <> ToString[list[[3]]], " days "}}, Alignment -> Left]

Answer 2

I would use Row instead of converting everything to a string and concatenating. Also, you can use the built-in Quantity system as well. So, something like:

list = {1, 2.2, 3.333};
Column[{
    Row[{"distance result = ", Quantity[list[[2]], "Meters"]}],
    Row[{"time result = ", Quantity[list[[3]], "Days"]}]
    },
    Alignment->"="
]

There are several issues when converting to a string. In your case, a problematic example is a number like 1.1*10^-6:

ToString[1.1*10^-6] //InputForm

(* "      -6\n1.1 10" *)