Calculate from the command line with Spigot

Conversion

Spigot supports conversion between numbering systems using various kinds of syntax. The command shown here will work in every case:

echo <valueI> | spigot -b<output_base> ,base
<input_base>fd:0'

Figure 4 shows common usage examples.

Figure 4: You can convert numbers using Spigot in several different ways.

Calculating Frequency

The example from Listing 2 shows how to deal with variables as exponents. Here you see that the variables are isolated by quotes; the e-12 describes the exponent's remainder. Use the script to calculate the frequency of a resonant circuit using the coil (Inductance , ?H ) and the capacitor (Capacitor , pF ). See Figure 5 for the script's output.

Listing 2

qrgcalc.sh

#!/bin/bash
# qrgcalc.sh
echo "Resonant circuit calculation, result in MHz"
read -p "Inductance in ?H: " L
read -p "Capacitor in pF: " C
echo "Inductance: $L ?H, Capacitor $C pF"
# In the header, correct conversion for ISO units to H and F
echo "------------------------------"
qrg=$(spigot --rn -d50 "$L"e-6*"$C"e-12 | spigot --rn -d50 '(1/(2pi*sqrt(base10fd:0))/1000000)' --printf %10.3f)
echo "Frequency $qrg MHz"