def plot(workspace, tokens=None):
    """When called from window.py it initiates rendering of equations.

    Arguments:
        workspace {QtWidgets.QWidget} -- main layout
    """
    from visma.io.tokenize import tokenizer

    workspace.figure2D.clear()
    workspace.figure3D.clear()
    if tokens is None:
        tokens = workspace.eqToks[-1]
    eqType = getTokensType(tokens)
    LHStok, RHStok = getLHSandRHS(tokens)
    variables = sorted(getVariables(LHStok, RHStok))
    dim = len(variables)
    graphVars, func, variables = graphPlot(workspace, False, tokens)
    renderPlot(workspace, graphVars, func, variables, tokens)
    if (dim == 1):
        var2, var3 = selectAdditionalVariable(variables[0])
        if tokens is None:
            workspace.eqToks[-1] += tokenizer("0" + var2 + "+" + "0" + var3)
        else:
            tokens += tokenizer("0" + var2 + "+" + "0" + var3)
    if (((dim == 2) or (dim == 1)) & (eqType == 'equation')):
        graphVars, func, variables = graphPlot(workspace, True, tokens)
        renderPlot(workspace, graphVars, func, variables, tokens)