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diff --git a/src/util/numeric/converters.h b/src/util/numeric/converters.h
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+// SPDX-License-Identifier: GPL-2.0-or-later
+/** @file
+ * Utility functions to convert ascii representations to numbers
+ */
+#ifndef UTIL_NUM_CONVERTERS_H
+#define UTIL_NUM_CONVERTERS_H
+/*
+ * Authors:
+ *   Felipe Corrêa da Silva Sanches <juca@members.fsf.org>
+ *   Mohammad Aadil Shabier
+ *
+ *
+ * Copyright (C) 2006 Hugo Rodrigues
+ *
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+
+#include <iostream>
+#include <cstring>
+#include <sstream>
+#include <vector>
+
+namespace Inkscape {
+namespace Util {
+
+// while calling read_number(string, false), it's not obvious, what
+// that false stands for. read_number(string, NO_WARNING)
+// can be more explicit.
+constexpr bool NO_WARNING = false;
+
+/* convert ascii representation to double
+ * the function can only be used to convert numbers as given by gui elements that use localized representation
+ * @param value ascii representation of the number
+ * @return the converted number
+ *
+ * Setting warning to false disables conversion error warnings from
+ * this function. This can be useful in places, where the input type
+ * is not known beforehand. For example, see sp_feColorMatrix_set in
+ * sp-fecolormatrix.cpp
+ * Consider making warning = True by default since that's how it seems to be used everywhere?
+ */
+inline double read_number(gchar const *value, bool warning = true)
+{
+    if (!value) {
+        g_warning("Called Inkscape::Util::read_number with value==null_ptr, this can lead to unexpected behaviour.");
+        return 0;
+    }
+    char *end;
+    double ret = g_ascii_strtod(value, &end);
+    if (*end) {
+        if (warning) {
+            g_warning("Inkscape::Util::read_number() Unable to convert \"%s\" to number", value);
+        }
+        // We could leave this out, too. If strtod can't convert
+        // anything, it will return zero.
+        ret = 0;
+    }
+    return ret;
+}
+
+inline bool read_bool(gchar const *value, bool default_value)
+{
+    if (!value)
+        return default_value;
+    switch (value[0]) {
+        case 't':
+            if (strncmp(value, "true", 4) == 0)
+                return true;
+            break;
+        case 'f':
+            if (strncmp(value, "false", 5) == 0)
+                return false;
+            break;
+    }
+    return default_value;
+}
+
+/* convert ascii representation to double
+ * the function can only be used to convert numbers as given by gui elements that use localized representation
+ * numbers are delimited by space
+ * @param value ascii representation of the number
+ * @return the vector of the converted numbers
+ */
+inline std::vector<gdouble> read_vector(const gchar *value)
+{
+    std::vector<gdouble> v;
+
+    gchar const *beg = value;
+    while (isspace(*beg) || (*beg == ','))
+        beg++;
+    while (*beg) {
+        char *end;
+        double ret = g_ascii_strtod(beg, &end);
+        if (end == beg) {
+            g_warning("Inkscape::Util::read_vector() Unable to convert \"%s\" to number", beg);
+            break;
+        }
+        v.push_back(ret);
+
+        beg = end;
+        while (isspace(*beg) || (*beg == ','))
+            beg++;
+    }
+    return v;
+}
+
+/*
+ * Format a number with any trailing zeros removed.
+ */
+inline std::string format_number(double val, unsigned int precision = 3)
+{
+    std::ostringstream out;
+    out.imbue(std::locale("C"));
+    out.precision(precision);
+    out << std::fixed << val;
+    std::string ret = out.str();
+
+    while(ret.find(".") != std::string::npos
+        && (ret.substr(ret.length() - 1, 1) == "0"
+         || ret.substr(ret.length() - 1, 1) == "."))
+        ret.pop_back();
+
+    return ret;
+}
+
+
+} // namespace Util
+} // namespace Inkscape
+
+#endif // UTIL_NUM_CONVERTERS_H
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :