Pyrrhus is only mentioned in Book XIX of the Iliad and that's under the name of Neoptolemus. He isn't mentioned anywhere else and never by that name. Are you reading the Iliad or another novel about the Trojan War?
Calchas is only mentioned in Book I of the Iliad, during which he says;
"The god," he said, "is angry neither about vow nor hecatomb, but for his priest's sake, whom Agamemnon has dishonoured, in that he would not free his daughter nor take a ransom for her; therefore has he sent these evils upon us, and will yet send others. He will not deliver the Danaans from this pestilence till Agamemnon has restored the girl without fee or ransom to her father, and has sent a holy hecatomb to Chryse. Thus we may perhaps appease him." (1)
Again, are you sure you want this question tagged under the questions and answers for the Iliad?