TCLspice consists of a library or a package to include in your tcl console or script:

load /somepath/libspice.so
package require spice

Then you can execute any native SPICE command by preceding it with spice::. For example if you want to source the testCapa.cir netlist, type the following:

spice::source testCapa.cir
spice::spicetoblt example...

Plotting data is not a matter of SPICE, but of tcl. Once the data is stored in a blt vector, it can be plotted. Example:

blt::graph .cimvd -title "Cim = f(Vd)"
pack .cimvd
.cimvd element create line1 -xdata Vcmd -ydata Cim

With blt::graph a plotting structure is allocated in memory. With pack it is placed into the output window, and becomes visible. The last command, and not the least, plots the function (C_{im} = f\left( V_{cmd} \right)), where (C_{im}) and (V_{cmd}) are two BLT vectors.