follicleがないhairSystemとpfxHairを見つけて選択するやつ

selectEmptyHair.py

# -*- coding: utf-8 -*-
import pymel.core as pm


def selectEmptyHairs():

    hairs = pm.ls(type='hairSystem')

    if len(hairs) is 0:
        pfxs = pm.ls(type='pfxHair')
        if len(pfxs) is 0:
            return 'Not found hairSystem and pfxHair.'
        else:
            # pfxHairShapeのtransformを選択
            pm.select(map(lambda p:p.getParent(), pfxs))
        return 'Not found hairSystem, But few found pfxHair.'

    selection = []
    for hair in hairs:
        follicles = hair.attr('inputHair').inputs()
        if len(follicles) is 0:
            selection.append(hair.getParent())
            pfxs = pm.listConnections(hair, source=False, type='pfxHair')
            selection.extend(pfxs)

    pfxs = pm.ls(type='pfxHair')
    for pfx in pfxs:
        try:
            hairs = pfx.attr('renderHairs').inputs()
            if len(hairs) is 0:
                selection.append(pfx.getParent())
        except:
            selection.append(pfx.getParent())

    if len(selection) is 0:
        return 'Not found empty hairSystem and empty pfxHair.'
    else:
        pm.select(selection)
        return 'Found empty hairSystem or pfxHair.'

maya/scriptsなどに保存してMayaのScriptEditor（PythonTab）へコマンドを打ち込む

from selectEmptyHair import selectEmptyHairs
selectEmptyHairs()