Adding a new class to represent methylation information associated wi…

…th individual sites.

src/common/MethpipeSite.cpp

@@ -0,0 +1,54 @@
+/*
+  Copyright (C) 2015 University of Southern California
+  Authors: Andrew D. Smith
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with This program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#include "MethpipeSite.hpp"
+
+#include <string>
+#include <iostream>
+#include <sstream>
+
+#include "smithlab_utils.hpp"
+
+using std::string;
+
+std::istream &
+operator>>(std::istream &in, MSite &s) {
+  string line;
+  if (!getline(in, line))
+    return in;
+
+  std::istringstream iss(line);
+  if (!(iss >> s.chrom >> s.pos >> s.strand
+        >> s.context >> s.meth >> s.n_reads))
+    throw SMITHLABException("bad methcounts file");
+  return in;
+}
+
+
+string
+MSite::tostring() const {
+  std::ostringstream oss;
+  oss << chrom << '\t'
+      << pos << '\t'
+      << strand << '\t'
+      << context << '\t'
+      << meth << '\t'
+      << n_reads;
+  return oss.str();
+}

src/common/MethpipeSite.hpp

@@ -0,0 +1,87 @@
+/*
+  Copyright (C) 2015 University of Southern California
+  Authors: Andrew D. Smith
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with This program; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef METHPIPE_SITE_HPP
+#define METHPIPE_SITE_HPP
+
+#include <string>
+#include <tr1/cmath>
+
+struct MSite {
+  std::string chrom;
+  size_t pos;
+  char strand;
+  std::string context;
+  double meth;
+  size_t n_reads;
+
+  size_t n_meth() const {return std::tr1::round(meth*n_reads);}
+
+  //////////////////////////////////////////////////////////////
+  /// FUNCTIONS BELOW ARE FOR MANIPULATING SYMMETRIC CPG SITES
+  //////////////////////////////////////////////////////////////
+  void add(const MSite &other) {
+    if (!is_mutated() && other.is_mutated())
+      context += 'x';
+    // ADS: order matters below as n_reads update invalidates n_meth()
+    // function until meth has been updated
+    const size_t total_c_reads = n_meth() + other.n_meth();
+    n_reads += other.n_reads;
+    meth = static_cast<double>(total_c_reads)/n_reads;
+  }
+
+  // ADS: function below has redundant check for is_cpg, which is
+  // expensive and might be ok to remove
+  bool is_mate_of(const MSite &first) {
+    return (first.pos + 1 == pos && first.is_cpg() && is_cpg() &&
+            first.strand == '+' && strand == '-');
+  }
+
+  ////////////////////////////////////////////////////////////////////////
+  /////  Functions below test the type of site. These are CpG, CHH, and
+  /////  CHG divided into two kinds: CCG and CXG, the former including a
+  /////  CpG within. Also included is a function that tests if a site
+  /////  has a mutation.
+  /////  WARNING: None of these functions test for the length of their
+  /////  argument std::string, which could cause problems.
+  ////////////////////////////////////////////////////////////////////////
+  bool is_cpg() const {
+    return (context[0] == 'C' && context[1] == 'p' && context[2] == 'G');
+  }
+  bool is_chh() const {
+    return (context[0] == 'C' && context[1] == 'H' && context[2] == 'H');
+  }
+  bool is_ccg() const {
+    return (context[0] == 'C' && context[1] == 'C' && context[2] == 'G');
+  }
+  bool is_cxg() const {
+    return (context[0] == 'C' && context[1] == 'X' && context[2] == 'G');
+  }
+  bool is_mutated() const {
+    return context[3] == 'x';
+  }
+
+  std::string tostring() const;
+
+};
+
+std::istream &
+operator>>(std::istream &in, MSite &s);
+
+#endif